CHAPTER XXX.

POSITION OF THE HOUSE.

Lord Bacon said: He who builds a fair house upon an ill seat committeth himself to prison.” The first considerations, therefore, in choosing a house are those of aspect, surrounding objects, and soil. On the first of these considerations, that of =aspect=, Thomas Fuller’s quaint remarks give the essential points. He says:

“Light (God’s eldest daughter) is a principal beauty in a building; yet it shines not alike from all parts of heaven. An east window welcomes the beams of the sun before they are of strength to do any harm, and is offensive to none but a sluggard. A south window in summer is a chimney with a fire in it, and needs the screen of a curtain. In a west window in summer towards night the sun grows low and even familiar, with more light than delight. A north window is best for butteries and cellars, where the beer will not be sour from the sun shining on it.”

A workroom or study requiring steady light, should point north or some point between north-east and north-west. A breakfast room should face north-east to south; while one aspect of a drawing-room should be south-east to north-east. Store-rooms, dairies, larders, should have a northerly aspect. It is preferable, as a rule, for the house not to face in the direction of the four points of the compass, but diagonally to these.

=Surrounding Objects= of an objectionable character, as factories, noisy or offensive trades are to be avoided. The possibility of neighbouring cesspools contaminating the water supply must be considered. _Trees_ close to a house are objectionable, rendering it damp, and preventing the free access of sun and air. More remote from the house they form a useful shelter, especially when to the north or east.

The banks of _water courses_ are to be avoided for similar reasons. If there is a choice, the _slope of a hill_ should be selected; and it is essential that no part of the dwelling should rest against sloping ground at a higher level. Rank vegetation indicates a damp clayey soil.

The main point is to secure that the house shall receive ample =light= and ventilation. In calculating the =amount and intensity of sunshine= which a house built on a given site will secure the variations according to season must be remembered. The direction (orientation) of the sun is the same all the year through; but the altitude of the sun varies with the latitude. Thus in a house facing directly south in the latitude of the south of England the sun’s altitude at noon on the 21st of December is 15° 4´, on the 21st of June 62° 4´. A ray of light entering the highest point of a window facing south at each of these seasons will illuminate a much larger part of the room in summer than in winter. Not only so, but inasmuch as it enters the room more nearly vertically it is more powerful than when entering at an angle more nearly approximating a horizontal direction, in accordance with the general law that the intensity of illumination falling on a horizontal surface (as the floor of a room) is inversely as the square of the width of the area embraced within the same angle of incidence of light.

In houses in a street the angular aperture through which light enters is greatest in the upper stories. It may be increased (_a_) by increasing the height of rooms; (_b_) by carrying the window heads nearly to the level of the ceiling; and (_c_) by avoiding the proximity of other buildings which would impede the access of light. Fig. 36 shows the importance of the last consideration. This represents a three-storied house in a street, of which the opposite house L is of the same height. It will be observed that each room is divided into two regions of different degrees of illumination by a plane Lm, formed by a line connecting the ridge of the roofs of the houses on the opposite side of the street with the interior surface of the rooms and touching the uppermost point of the window in transit. Below this line there is “sky-light” sufficient in quantity; above this line light is insufficient in amount and is diffused and reflected. The area receiving sufficient light increases from the ground floor upwards. We have already seen that its intensity similarly increases in the higher stories, the rays of light being more nearly vertical in these.

The amount of sky-light visible can be expressed in terms of the _angle of aperture_, i.e. the arc of sky visible at any given point _a_ in the room. Thus in Fig. 36 the triangle of aperture _bac_ is greater than _b´a´c´_, and this greater than _b´´a´´c´´_. The sides of the angle of aperture, it will be seen, are formed by drawing one line from the point a to c, which, if prolonged, would touch L, and another line to _b_, which passes through the highest point of the window.

The amount of light received in a dwelling-house is largely determined by the =width of the street= and the distance between the backs of the houses in adjacent streets. The model Bye-laws of the Local Government Board insist that no new street shall be less than 36 feet wide if it exceeds 100 yards in length or is intended to be a carriage road, not less than 24 feet in any case. Furthermore, a new house must have in the rear an open space exclusively belonging to the house, at least 150 square feet in area, and free from any erection above the ground level. This must extend along the entire width of the house, and must never measure less than 10 feet from every part of the back wall of the house; the distance must be at least 15 feet, if the house is 15 feet high; 20 feet if 25 feet high, and 25 feet if 35 feet high or more.

Streets should never be less in width than the height of the houses in them; and a line drawn from the ridge of the roof to the foot of the wall of the opposite houses (Fig. 37) or in the rear to the foot of the wall or fence dividing the back yards of contiguous houses, should not make an angle of more than 45º with the ground (Fig. 37). This is the angle required for new buildings in the residential parts of Liverpool, and was proposed for London, but unfortunately not made obligatory. The size of windows is discussed on page 216. The light received in a given house is often diminished at corners of streets by contiguous houses.

The =Soil= has an important influence on the healthiness of a site. The relative merits of the different kinds of soil are discussed on page 219. Undrained soils of whatever kind are bad, and made-soils are always to be regarded with profound distrust.

The =planning= of a house should be carefully considered. The principle is that the sun should enter every living room at some time of the day. The relative positions of fire-place, window, and door in each room are important. With the sole window of a room in the same wall as the fire-place the area ventilated is the least, with it situated on the opposite wall the area ventilated is the greatest. The door should be as remote from the window as possible, in order to secure occasional perflation of air; the two being preferably on opposite walls. Staircase windows are indispensable to secure through ventilation of a dwelling. Houses constructed “back to back” cannot be properly ventilated as no through current of air is possible. Hence the necessity for open yards at the area, as well as air-space in front of the house. (Fig. 37).

In the =construction= of a house, apart from access of light and air, the main problems are to secure dryness and equability of temperature. We shall consider in this connection the materials used in the construction of walls, floors, and roofs.